/**

 * Copyright (c) Meta Platforms, Inc. and affiliates.

 *

 * This source code is licensed under the MIT license found in the

 * LICENSE file in the root directory of this source tree.

 *

 * @flow

 */

import {disableLegacyContext} from 'shared/ReactFeatureFlags';

import getComponentNameFromType from 'shared/getComponentNameFromType';

import checkPropTypes from 'shared/checkPropTypes';

let warnedAboutMissingGetChildContext;

if (__DEV__) {

  warnedAboutMissingGetChildContext = ({}: {[string]: boolean});

}

export const emptyContextObject: {} = {};

if (__DEV__) {

  Object.freeze(emptyContextObject);

}

export function getMaskedContext(type: any, unmaskedContext: Object): Object {

  if (disableLegacyContext) {

    return emptyContextObject;

  } else {

    const contextTypes = type.contextTypes;

    if (!contextTypes) {

      return emptyContextObject;

    }

    const context: {[string]: $FlowFixMe} = {};

    for (const key in contextTypes) {

      context[key] = unmaskedContext[key];

    }

    if (__DEV__) {

      const name = getComponentNameFromType(type) || 'Unknown';

      checkPropTypes(contextTypes, context, 'context', name);

    }

    return context;

  }

}

export function processChildContext(

  instance: any,

  type: any,

  parentContext: Object,

  childContextTypes: Object,

): Object {

  if (disableLegacyContext) {

    return parentContext;

  } else {

    // TODO (bvaughn) Replace this behavior with an invariant() in the future.

    // It has only been added in Fiber to match the (unintentional) behavior in Stack.

    if (typeof instance.getChildContext !== 'function') {

      if (__DEV__) {

        const componentName = getComponentNameFromType(type) || 'Unknown';

        if (!warnedAboutMissingGetChildContext[componentName]) {

          warnedAboutMissingGetChildContext[componentName] = true;

          console.error(

            '%s.childContextTypes is specified but there is no getChildContext() method ' +

              'on the instance. You can either define getChildContext() on %s or remove ' +

              'childContextTypes from it.',

            componentName,

            componentName,

          );

        }

      }

      return parentContext;

    }

    const childContext = instance.getChildContext();

    for (const contextKey in childContext) {

      if (!(contextKey in childContextTypes)) {

        throw new Error(

          `${

            getComponentNameFromType(type) || 'Unknown'

          }.getChildContext(): key "${contextKey}" is not defined in childContextTypes.`,

        );

      }

    }

    if (__DEV__) {

      const name = getComponentNameFromType(type) || 'Unknown';

      checkPropTypes(childContextTypes, childContext, 'child context', name);

    }

    return {...parentContext, ...childContext};

  }

}